Spectroquant Pharo 300 - Page 386

Measuring 0.0005 – 0.5000 mg/l SiO
2
0.0002 – 0.2337 mg/l Si 50-mm cell
range: Expression of results also possible in mmol/l.
Silicate (Silicic Acid)
101813
Test
Select method with
AutoSelector.
Reaction time:
5 minutes
Check the pH of the
sample, specified range
:
pH 2– 10.
If required, add dilute
sodium hydroxide
solution or sulfuric acid
drop by drop to adjust
the pH.
Add to each vessel
0.50 ml of Si-3 with
pipette, close with the
screw cap, and mix.
Add to each vessel
3 drops of Si-1,
close with the screw
cap, and mix.
Quality assurance:
To check the measurement system (test reagents, meas-
urement device, and handling) ready-f
or-use silicon stan-
dard solution
Certipur
®
, Cat.No. 170236, concentration
1000 mg/l Si, can be used after diluting accordingly
(Atten tion! Do not store standard solutions in glass
vessels - see section "Standard solutions").
Pipette 10 ml of the
sample into a plastic
vessel (Flat-bottomed
tubes, Cat.No. 117988).
Pipette 10 ml of distilled
water (Water Ultrapur,
Cat.No. 101262, is
recommended) into a
second plastic vessel
(Flat-bottomed tubes,
Cat.No. 117988).
(Blank)
Check the pH, specified
range
: pH 1.2 – 1.6.
Add to each vessel
3 drops of Si-2,
close with the screw
cap, and mix.
Transfer the blank into a
rectangular cell and
measure immediately.
Important:
No glass equipment may be used in the course of the
determination (e
. g. pipettes etc.)!
Transfer the measure-
ment sample into a
rectangular cell and
measure immediately.
Insert the cell containing
the sample into the cell
compartment.
Insert the blank cell into
the cell compartment.
Reaction time:
5 minutes
Release 06/2014 - Spectroquant
®
UV/VIS Spectrophotometer Pharo 300
Configure the photometer
for blank-measurement.